摘要
选用过硫酸铵APS作为引发剂,水作为溶剂,通过沉淀自由基接枝聚合引发棉纤维接枝PNIPAAm。红外分析和电镜观察均表明棉已成功接枝上PNIPAAm,获得了棉纤维接枝PNIPAAm共聚物(接枝棉);采用质量法计算接枝棉的接枝率,并研究了单体和引发剂浓度对接枝率的影响;MDSC测试表明接枝棉在PNIPAAm的LCST附近(33℃)显示了温敏性,且对应的可逆焓变随接枝率的增大而增大。通过测量不同环境温度下水滴在接枝棉表面的接触角表征接枝棉的温敏亲/疏水性,并研究了接枝率对接枝棉的温敏亲/疏水性影响。通过滴水试验(AATCC 79-2000标准)测量不同环境温度下水滴完全浸入接枝棉的浸润时间表征了接枝棉的温敏吸水性。该接枝体系组成简单,操作容易,所选水溶剂对环境无污染、环保。
In this paper,ammonium peroxydisulfate（APS）was selected as initiator to initiate cotton to be grafted poly（N-isopropyl acrylamide）（PNIPAAm）in water solvent by free-radical precipitating grafting polymerization.FTIR-ATR analysis and SEM analysis showed that PNIPAAm was successfully grafted onto the cotton,obtained cotton-grafted-PNIPAAm.The grafting degree of cotton-grafted-PNIPAAm was calculated by the weight change of cotton before and after grafted modification,and it was affected by the concentration of monomer and initiator.MDSC test proved the thermo-responsive function of cotton-grafted-PNIPAAm around 33℃,whose reversing enthalpy change increased with the grafting-degree increase.Water contact angle test also showed the thermo-responsive hydrophilicity/hydrophobicity of cotton-grafted-PNIPAAm,which was barely influenced by their grafting degree.The water wetting time of cotton-grafted-PNIPAAm can characterize their thermo-responsive absorbency,which has been tested by water absorbency test（AATCC 79-2000）below and above the LCST respectively.This grafting polymerization owned simple constituent,water selected as an eco-friendly solvent and can be operated easily.
基金
国家自然科学基金(51463005)
贵州省科学技术基金(黔科合J字[2014]2051)
贵州省科学技术基金(黔科合J字[2014]2054)
贵州省研究生教育创新计划项目(黔教研合JYSZ字[2014]001)
关键词
过硫酸铵
聚N-异丙基丙烯酰胺
棉纤维
温敏亲/疏水性
沉淀自由基接枝聚合
ammonium peroxydisulfate（APS）
poly（N-isopropyl acrylamide）（PNIPAAm）
cotton
thermoresponsive hydrophilicity/hydrophobicity
free-radical precipitating grafting polymerization
